Fixed ClusterDaemon log formatting errors

There were some incorrect format strings published by the ClusterDaemon
to the logging system that would cause the logger to crash. This
corrects the format strings and also swaps in the correct `Warning`
method for `Warn` where applicable.
Merge pull request #490 from Aaronontheweb/akka-cluster-logging-fixes

Fixed ClusterDaemon log formatting errors